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                                                                   EXHIBIT 10.20

                               THIRD AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT


         THIS THIRD AMENDMENT TO RECEIVABLES PURCHASE AGREEMENT, dated as of
July 2, 2003 (this "Amendment"), is entered into among ATRIUM FUNDING CORP., a
Delaware corporation, as seller (the "Seller"), ATRIUM COMPANIES, INC., a
Delaware corporation, as initial servicer (in such capacity, together with its
successors and permitted assigns in such capacity, the "Servicer"), FAIRWAY
FINANCE CORPORATION, a Delaware corporation (the "Purchaser"), and BMO NESBITT
BURNS CORP., a Delaware corporation as agent for the Purchaser (in such
capacity, together with its successors and assigns in such capacity, the
"Agent").

                                   BACKGROUND

         1. The Seller, the Servicer, the Purchaser and the Agent are parties to
that certain Receivables Purchase Agreement, dated as of July 31, 2001 (as
amended through the date hereof, the "Receivables Purchase Agreement").

         2. The parties hereto desire to amend the Receivables Purchase
Agreement as set forth herein.

         NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto hereby agree as follows:

         SECTION 1. Definitions. Capitalized terms used in this Amendment and
not otherwise defined herein shall have the meanings assigned thereto in the
Receivables Purchase Agreement.

         SECTION 2. Amendment. The definition of "Purchase Limit" is hereby
amended by deleting the number "$42,000,000" where it appears therein and
replacing it therewith by "$50,000,000".

         SECTION 3. Miscellaneous. This Amendment may be executed in any number
of counterparts and by the different parties on separate counterparts, each of
which when so executed shall be deemed to be an original and all of which when
taken together shall constitute one and the same agreement. This Amendment shall
be governed by, and construed in accordance with, the internal laws of the State
of New York. The Receivables Purchase Agreement, as amended hereby, remains in
full force and effect. Any reference to the Receivables Purchase Agreement after
the date hereof shall be deemed to refer to the Receivables Purchase Agreement
as amended hereby, unless otherwise expressly stated therein.

                            [signature pages follow]



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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective, duly authorized officers as of the date and year
first-above written.

                                                 ATRIUM FUNDING CORP., as Seller


                                                 By:
                                                    ----------------------------
                                                 Name Printed:
                                                              ------------------
                                                 Title:
                                                       -------------------------


                                      S-1

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                                                 ATRIUM COMPANIES, INC.,
                                                 as Servicer


                                                 By:
                                                    ----------------------------
                                                 Name Printed:
                                                              ------------------
                                                 Title:
                                                       -------------------------





                                      S-2

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                                                 BMO NESBITT BURNS CORP.,
                                                 as Agent


                                                 By:
                                                    ----------------------------
                                                 Name Printed:
                                                              ------------------
                                                 Title:
                                                       -------------------------


                                                 By:
                                                    ----------------------------
                                                 Name Printed:
                                                              ------------------
                                                 Title:
                                                       -------------------------



                                      S-3

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                                                 FAIRWAY FINANCE CORPORATION,
                                                 as Purchaser


                                                 By:
                                                    ----------------------------
                                                 Name Printed:
                                                              ------------------
                                                 Title:
                                                       -------------------------


                                      S-4